The present invention relates generally to broadcast television systems, and more particularly, to the recording of programs and incorporation of previously broadcast content into the recording.
A broadcast service provider generates audio-video streams for transmission to a viewer""s television. Interactive television systems are capable of displaying text and graphic images in addition to typical audio-video program streams and provide a number of services and interactive applications to viewers. The interactive television signal includes an interactive portion consisting of application code or system information, as well as an audio-video portion consisting of a television program. The broadcast service provider combines the audio-video and interactive portions into a single signal for transmission to a receiver connected to the viewer""s television. The signal is generally compressed prior to transmission and transmitted through typical broadcast media such as cable television (CATV) lines or direct satellite transmission systems.
A set top box connected to the television controls the interactive functionality of the television. The set top box receives the signal transmitted by the broadcast service provider, separates the interactive portion from the audio-video portion, and decompresses the respective portions of the signal. The set top box uses interactive information to execute an application while the audio-video information is transmitted to the television.
Set top boxes typically include only a limited amount of memory. While this memory is sufficient to execute interactive applications, it is typically not adequate to store the applications for an indefinite period of time. Further, the memory of the set top box is typically too small to accommodate a program which includes large amounts of audio or video data, application code, or other information. Storage devices may be coupled with the set top box to provide additional memory for the storage of video and audio broadcast content.
Interactive content such as application code or information relating to television programs is typically broadcast in a repeating format. The pieces of information broadcast in this manner form what is referred to as a xe2x80x9ccarouselxe2x80x9d. Repeating transmission of objects in a carousel allows the reception of those objects by a receiver without requiring a return path from the receivers to the server. If a receiver needs a particular piece of information, it can simply wait until the next time that piece of information is broadcast, and then extract the information from the broadcast stream. If the information were not cyclically broadcast, the receiver would have to transmit a request for the information to the server, thus requiring a return path. If a viewer is initially not interested in the carousel content, but later expresses an interest, the information can be obtained the next time the carousel is broadcast.
Since broadcast networks have access only to a limited bandwidth, audio-video content is not broadcast in carousels. Thus, the set top box cannot wait to receive the rebroadcast of the audio and video content if a viewer decides to record a program after it has already started. There is also insufficient bandwidth and server resources to handle pulling of large amounts of data required for video and audio in real-time to handle near simultaneous requests for broadcast of previously broadcast material from a vast number of television viewers. Therefore, even if sufficient storage is available on the storage device, a viewer cannot decide in the middle of a program to record the entire program, since the beginning of the program has already been broadcast. Thus, a viewer who wants to record an entire program must decide to do so before broadcast of the program has started. The viewer also has to prepare the media for recording before the start of a program. This may require deleting one or more previously recorded programs or attaching an external storage device. Since the viewer has not yet seen any of the program, it may be difficult for the viewer to choose to delete one or more of the existing recordings to make space for the new program.
There is, therefore, a need for a system and method that allows a viewer to record an entire broadcast program after a portion of it has already been viewed.
A method and system for incorporating previously broadcast content into a recording of a program are disclosed. A method of the present invention generally comprises receiving a broadcast containing a program and automatically recording the broadcast at a start of the program to store a first portion of the program in a first storage area. A space within a second storage area is allocated upon receiving a record command during the recording of the first portion of the program. A second portion of the program is recorded in the allocated space in the second storage area.
The first storage area may be a circular buffer which temporarily stores the first portion of the program broadcast prior to a viewer deciding to record the program. The first and second storage area may comprise a magnetic disk, optical disk or flash memory, for example. The first and second storage areas may be located in a storage device coupled to a set top box or located internal to the set top box. If a space sufficient in size to store the entire program is available on the storage device, the space is allocated for the program. The second portion of the program is recorded in the allocated space and the first portion of the program is transferred from the circular buffer to the allocated space to create a program recording. The common storage area may be the allocated space in the second storage area, a new space within the second storage area, or a completely different storage area. If there is insufficient space to record the entire program on the storage device, a viewer of the program will be notified. The viewer may delete previously recorded material from the storage device or cancel the request for recording the current program.
A system of the present invention generally comprises a receiver operable to receive the program, a storage device coupled to the receiver, and a processor. The processor is operable to automatically control the recording of the program in order to store a first portion of the program in a first storage area, allocate space within the storage device after the start of the program, direct a second portion of the program to the allocated space of the second storage area, and combine the first and second portions of the program.
The receiver may be a set top box and the storage device may be contained within the set top box or may be a storage device externally connected to the set top box. The first storage area may be located within the set top box or the storage device.